Tyler M A, Ulasov I V, Sonabend A M, Nandi S, Han Y, Marler S, Roth J, Lesniak M S
Division of Neurosurgery, The Brain Tumor Center, The University of Chicago, Chicago, IL 60637, USA.
Gene Ther. 2009 Feb;16(2):262-78. doi: 10.1038/gt.2008.165. Epub 2008 Dec 11.
Adenoviral oncolytic virotherapy represents an attractive treatment modality for central nervous system (CNS) neoplasms. However, successful application of virotherapy in clinical trials has been hampered by inadequate distribution of oncolytic vectors. Neural stem cells (NSCs) have been shown as suitable vehicles for gene delivery because they track tumor foci. In this study, we evaluated the capability of NSCs to deliver a conditionally replicating adenovirus (CRAd) to glioma. We examined NSC specificity with respect to viral transduction, migration and capacity to deliver a CRAd to tumor cells. Fluorescence-activated cell sorter (FACS) analysis of NSC shows that these cells express a variety of surface receptors that make them amenable to entry by recombinant adenoviruses. Luciferase assays with replication-deficient vectors possessing a variety of transductional modifications targeted to these receptors confirm these results. Real-time PCR analysis of the replication profiles of different CRAds in NSCs and a representative glioma cell line, U87MG, identified the CRAd-Survivin (S)-pk7 virus as optimal vector for further delivery studies. Using in vitro and in vivo migration studies, we show that NSCs infected with CRAd-S-pk7 virus migrate and preferentially deliver CRAd to U87MG glioma. These results suggest that NSCs mediate an enhanced intratumoral distribution of an oncolytic vector in malignant glioma when compared with virus injection alone.
腺病毒溶瘤病毒疗法是治疗中枢神经系统（CNS）肿瘤的一种有吸引力的治疗方式。然而，溶瘤病毒载体分布不足阻碍了病毒疗法在临床试验中的成功应用。神经干细胞（NSCs）已被证明是合适的基因传递载体，因为它们能追踪肿瘤病灶。在本研究中，我们评估了神经干细胞将条件性复制腺病毒（CRAd）递送至胶质瘤的能力。我们研究了神经干细胞在病毒转导、迁移以及将CRAd递送至肿瘤细胞方面的特异性。对神经干细胞进行荧光激活细胞分选仪（FACS）分析表明，这些细胞表达多种表面受体，使得它们易于被重组腺病毒感染。对具有针对这些受体的多种转导修饰的复制缺陷型载体进行荧光素酶检测证实了这些结果。对神经干细胞和代表性胶质瘤细胞系U87MG中不同CRAds的复制情况进行实时PCR分析，确定CRAd - Survivin（S）- pk7病毒为进一步递送研究的最佳载体。通过体外和体内迁移研究，我们发现感染CRAd - S - pk7病毒的神经干细胞能够迁移并优先将CRAd递送至U87MG胶质瘤。这些结果表明，与单独注射病毒相比，神经干细胞可介导溶瘤病毒载体在恶性胶质瘤中的瘤内分布增强。
